Roller cam in older LA 318?

[Mopar92]

Can magnum hyd roller lifters be used in a mild street cam roller cam setup? Looking at roller cam/kits and they are very expensive!!! Just seeing what is interchangeable and what isn't with the new style roller lifters and the old blocks. Thanks.

 

[70aarcuda]

An older LA engine 318 ..340..360 can not use the magnum style roller lifter ...the new magnum blocks have bolt holes for the spider that hold the lifters in their bore...the LA engine does not....

you can find a new style LA engine 85 and up 318 had the OEM roller lifters.....

 

[70aarcuda]

if you are talking about putting magnum roller lifters in a 318 roller motor...then the answer is yes......the main thing is the lifter valley designed for the oem roller lifters...otherwise you have to use the retro roller lifters..

 

[Mopar92]

Its a 1974 engine. I suppose I can just put a new cam and lifters and pray like crazy I don't wipe the lobes and kill the cam. Just seems like a dumb way to go nowdays.

 

[70aarcuda]

I dont know..i have several flat tappet cams working pretty good...

 

[Mopar92]

I've yet to wipe one. Just thought it might be a nice upgrade.

 

[nm9stheham]

Agreed it would be a nice upgrade.... and agreed it is costly! Flat tappets will be around for a while due to the cost. If you keep the cam mild and spring pressures down, then you will likely be just fine. IMO, some of the cam problems come from the newer high lift cams over .500" lift, and the more aggressive profiles, along with high pressure springs to reach higher RPM ranges. They can be made to work, but as lifter-to-lobe pressures go up, so do the odds of a problem.

 

[Mopar92]

Yeah I've always removed the inner springs for initial break in on the big bumps. I feel like it's Russian rullet. Perhaps I've just heard more horror stories than successful ones over the years. Haha

 

[goldduster318]

Yeah, you're stuck with the retrofit roller lifters in your block. They do work well.

The conversion is expensive, but I can't say I have ANY complaints about it

 

[nm9stheham]

OK, We went with a Crane SMB cam for my son's recent 340 build, partly because the cam profile is less aggressive on the ramps. I like the Voodoo and similar type profiles for operation, but was mildly concerned with the ramp rates.

I bet it is like complaints in general; people are going to talk about a failure far more often than a success.

 

[magnummopar]

FYI, if you want a roller cam, it might actually be less expensive to get a Magnum block with roller cam for a few hundred bucks than get a roller cam for your la engine. Lots of guys grabbing up magnums for under $400 these days. Just an alternative idea....

 

[middleagecrisis]

Yeah I've always removed the inner springs for initial break in on the big bumps. I feel like it's Russian rullet. Perhaps I've just heard more horror stories than successful ones over the years. Haha

People are more likely to post that they had a cam go flat during break-in, than to post saying everything went okay. I've broken in (properly) many hydraulic FT cams and never had a problem. Make sure the lifters rotate properly in the bores, and follow proper break in procedures and you'll probably be just fine.